Connecting plug



Dec. 3l, 1929. w. K. FLEMING CONNECTING PLUG Filed May 5 1928 Z/ ,//f/f/M INVENTOR. 14./ ,Q f2 Mm/G @im Patented Dec. 31, 1929 UNITED STATES PATENT OFFICEl WILFRED K. FLEMING, 0F CAMBRIDGE, MASSACHUSETTS, ASSIGNOR, BY MESNE AS- SIGNMENTS, T0 TOBE 'WARE Application led May 5,

This invention relates to connecting plugs and has particular reference to plugs to which the radio frequency circuit o a radio set may be connected. The line wires supplying electricity in homes have been used as antennae and ground for radio transmit ting and receiving sets. In order to establish the necessary connections between the set and line, it has been customary to insert one or more condensers of small capacity between the set and line wires. Line currents will be effectively kept out while radio frequency currents will have no difficulty in going through. It has been customary to connect both antennae and ground connections in this Wllfithin a house, the line usually has all its possible connections to consumption circuits by'means of standard outlet plugs, sockets, etc. As a rule, a room has but one wall outlet. vWhere a radio set requires connection for power supply in additon to antenna and ground connections and where portable lamps are in use, it is obvious that one such outlet usually has various multi-outlet plugs connected to each other and a tangle of wire in its neighborhood. lVhere connection from the radio set to an outlet was desired for the radio frequency circuits only, it has been customary to have a plug, one end of which was adapted to make a detachable connection with standard outlets or sockets while the other end had one or more terminals to which the antenna and ground connections could be made. This resulted in the complete monopolization of an outlet. Where a set has filament and plate supply-means obtaining power from the lighting circuit, the use of one outlet by the antenna-ground circuit would result in a multiplicity of plugs, a taugle of wire and generally in an unsightly appearance.

Objects of my invention are to eliminate and avoid the complete monopolization of an outlet by an antenna-ground connection; to provide a simple, compact, easily and cheaply made plug which will allow of the use of an outletfor antenna connections and consolidate the functions of two or more DEUTSCHMANN CORPORATION, A CORPORATION OF DELA- CONNECTING PLUG 1928. Serial No. 275,515.

plugs of present construction in a single, simple, and highly effective plug. vFurther ob- ]ects are to improve the construction of antenna plugs in general so that they are simple, 'I

Referring to Figure 1, there is vshown a plug generally designated by 1 and comprismg inlet and outlet portions 2 and 3. Inlet l portion 2 is adapted to make connection with a power outlet by means of two prongs 4 and 5 of standard construction.v Outlet portion 8 has sockets 6 and 7 in each of which are bent spring members 8 and 9, also of standard construction. Connection may be made to outlet portion 3 by a plug having two prongs similar to those of the inlet portion. Between inlet and-outlet portions 2 and 3 is a median portion 10. This portion is preferably of insulating material and comprises a cylindrical shell suitably molded at each end so that portions 2 and 3 may be fitted to it. The entire assembly is held together by screw 20 engaging a nut at one end. Shell 10 carries two terminals l1 and 12 adapted for connection to antenna and ground connections of a radio set. Theseterminals are fastened in any suitable manner to shell 10 and as shown are bolted by nuts on the inside of the shell. Each of these terminals carries on the inside of the shell bent spring members 13 and 14 which are adapted to make 'a irm Contact with the outside of condensers l5 and 16. 17 and 18 are elongated metallic lmembers preferably of brass which are integral with prongs 5 and 4 respectively.

bers 8 and 9 for connection with an outlet circuit. Thus both metallic members comprise a through connection from the inlet to the outlet portion of the plug.

Around members 17 and 18 are wound condensers 15 and 16 so that one pole of each contacts with the corresponding member and the other pole is bare to contact with the spring members 13 and 14.

In assembling the plug, shell 10 is provided with terminals 11 and 12 and spring members 13 and 14. Outlet portion 3 is inserted at the proper end of shell 10 and members 17 and 18 are fitted into holes 6 and 7 so that spring membersf8 and 9 are positioned as shown. When metallic members 17 and 18 are thus disposed, condensers 15 and 16 automatically engage spring members 13 and 14. Inlet portion 2 is then slipped over prongs 4 and 5 and fitted into' place and the entire assembly is maintained by bolt 20. If

desired, portion 2 may be fitted into place first and members 17 and 18 then slipped in from the other end of shell 10.

In Figure 2, substantially the same construction is shown except that inlet portion 21 is adapted to have a cord from a power circuit connected through hole 22 to metallic members inside corresponding to 17 and 18 of Figure 1. In this construction, the two prongs 4 and 5 of Figure 1 would be replaced by screws tapped into the brass members for the wires to make connection thereto. Outlet portion 31 comprises two outlet prong sockets 32 and 33. This construction is well known and could very easily be added on to the lower portion of members 17 and 18 of Figure 1 to replace the single outlet construction of that ligure.

Figure 3 shows condensers 15 and 16 with their poles soldered to members 17 and 18 and 11 and 12 respectively.

It is obvious that outlet portions 2 or'21 may take any variety of well known plug or socket construction and could be a screw or bayonet plug. Inlet portion 2 or 21 could also have a two-way construction, as shown in the outlet portion of Figure 2, thereby enabling a connection to be made at the inlet side of the plug with a power consumption clrcuit.

The same applies to outlet portions 3 and 31. These could be either plug or socket construction and take on any of the well known standard forms. The outlet portion could also be adapted to have wires directly connected to it instead of having a detachable connection.

Condensers 15 and 16 might also be wound around members 17 and 18 as shown in Figure 1 and soldered to terminals 11 and 12 as shown in Figure 3 if found desirable. These condensers are not necessarily of equal capacity and are preferably of such a capacity that radio frequency currents will ibe able to pass from members 17 and 18 to terminals 11 and 12 without any difficulty while currents of substantially lower frequency will be kept out.

In case outlet portion 3 or 31 does supply power to the radio set in addition to the high frequency impulses from terminals 11 and infinies 12, it is perfectly feasible to soarrange the inlet circuit so that plug 1 is brought very close to the set. In fact if desired, the entire plug may be disposed within the radio cabinet. In this way, antenna and ground connections :from the set to terminals 11 and 12 may be made very short. Hence, avery simple, neat and ei'ective line wire connection may be made with the radio set for all purposes desired.

W'ith the construction shown, it is evident that the plug may be made with a minimum of material, most of which is of standard construction in use in standard fixtures. Thus it will be seen that I have devised an antenna plug which is cheap, durable, simple, easily and quickly assembled, and has connections for radio and lighting circuits while at the same time permitting oi the normal use of the outlet for power consumption purposes.

I claim:

1. As an article of manufacture, a connecting plug comprising a plurality of metallic members, each member having means at both ends for connection to an electric circuit, a plurality of condensers, each condenser being woundaround a metallic member and having one pole connected to it, the other pole being exposed on the outside of each condenser, a plurality of spring members carried by the plug, each spring member contacting with the exposed pole of each condenser, and means on said spring members for connection to a radio set.

2. As an article of manufacture, a connecting plug comprising a hollow cylindrical insulating shell, a plurality of terminals carried by said shell, each terminal having a spring member inside the shell, two elongated metal members within the shell, each member having a condenser wound around it, and having oneof its poles connected thereto, the other pole adapted to contact with a spring member, and connecting means at each end of both metal members adapted to connect each end of said plug to a standard lighting circuit.

3. An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends ofsaid shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof, said members having means at both ends for detachable connection with standard lighting fixtures, a pair of condensers connected between each of said members and said terminals, and means to retain at .least one of the closures tightly against the shell and maintain the members in predetermined relative position.

4. An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends of said shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof, said members having means at both endsfor detachable connection with standard lighting fixtures, a pair of condensers connected between each of said members and said terminals, and means axially disposed within said shell to retain at least one of the closures tightly against the shell and maintain the members in predetermined relative position.

5. An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends of said shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof, a pair of condensers connected between each of said members andsaid terminals,said closures cooperating with said members to retain them in predetermined position.

6. An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends of said shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof. a pair of condensers connected between each of said members and said terminals, said closures cooperating with said members to retain them in predetermined position, and means axially disposed within said shell to retain at least one of said closures in a desired position.

7 An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends of said shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof, a pair of condensers connected between each of said members and said terminals, one of said closures cooperating with the connecting means at one end of said members to retain said members in predetermined position.

8. An antenna plug, comprising a cylindrical shell, a pair of terminals mounted thereon, closures for both ends of said shell, a pair of substantially rigid metal members disposed within the shell and parallel to the axis thereof, a pair of eondensers connected between each of said members and said terminals, one of said closures cooperating with the connecting means at one end of said members to retain said members in predetermined position, and means axially disposed within said shell to retain at least one of said'closures in desired position.

In testimony whereof, I have signed my name to this specification.

WILFRED K. FLEMING. 

